The differences between the CD63 and the -KI are mainly mechanical, and the KI has a toroidal transformer.
The CD63KI uses the same PCB as far as I know, so the tweaks apply to the KI also. It's possible that a few components (like caps) have a bigger value already, but you can replace them with better low-ESR types.

Originally posted by 6h5c I'd like to donate my files to this forum, for all to enjoy!

Thank you very much for sharing this fantastic list of modifications.

I too have a CD63ki and I have used an Audiocom clock with a dedicated external supply, I installed new op-amps (OPA627bp), and have changed or removed dozens of other components (eg. removed muting transistors and dc blocking caps). The sound is very good.

I have yet to play with the regulators, but this is something I'll look at soon. Also, I have not touched the HDAM, yet.

From your PDF:
"the HDAM-circuit looks nice, but when moving up to better opamps and interconnects this circuit starts to
interfere and degrades sound quality. To disable HDAM: remove R651...654 (+/- 12V), R617/618 and
RH23/24. Insert wire jumper at R619/620."

I have good op-amps and interconnects etc., so it is time to try this mod. Without having the service manual in front of me, I cannot picture how your changes bypass the HDAM - does the wire jumper from R619/20 bypass the whole circuit, if so where does it connect, at the phono sockets?

Originally posted by rowemeister The four resistors R651 - 654 supply the two HDAM circuits with +/- 12V.

Ok, nice. Better lift those then.

Quote:

Originally posted by rowemeister R617 and 618 are the audio input resistors, these need removing to stop audio entering the HDAM.

Fantastic, yoink they'll go!

Quote:

Originally posted by rowemeister RH23 and 24 are the output resistors from the HDAM, removing these prevents audio going backwards into the HDAM.

Splendid, a similar fate awaits said carbon devices.

Quote:

Originally posted by rowemeister Resistors R619/620 bypass the whole HDAM (like in the CD43/53)

This was the part I understood less well - how can there exist resistors that bypass it when it's not meant to be bypassed in this player? Are these just not connected normally then? Just unused spaces?

I may even pop the hood this evening and have a tinker. I'll probably break it